If you do more diseases, make them only communicable at close range. It would be much more fun to RP "keeping your distance from the guy in the corneer scratching himself vigourously", rather than just walking into an area and catching it without a single person in sight.

I know some diseases are airborne, but a lot are not, and should only be caught at very close range, e.g. talking to someone ("whisper range") or bartering with someone, etc.

PS: Any connection between Silks diseases and the increased lag of late ?

How about cramps in legs,
Players fall and walk diagonally to the left or right even though they want to walk forwards...

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Or some annoying 'I need to follow that guy' syndrome, where people force follow others around.

- As you gaze unknowingly into the seemingly infinite depths of the optics of this altogether passionate embodiment of insatiability, you experience a gradual realisation that the heavily-embellished vocabulary scattered lavishly throughout the sentence you are currently reading is indisputably nothing greater than a generous ration of masculine bovine faeces.